Coil winding machine



Sept. 4, 1956 o. J. WIRTH con. WINDING MACHINE Filed Dec. 21, 1955 \N INVENTOR.'- T I /5 km, MA

QA/M, ATTORNEY5.

United States Patent i COIL WINDING MACHINE Otto Jakob Wirth, Zurich, Switzerland, assignor to Micafil A.-G., Zurich-Alstetten, Switzerland- Application December 21, 1953, Serial No. 399,516 Claims priority, application Switzerland June 11, 1953 10 Claims. 01. 242-4 This invention relates to coil winding machines, and more particularly to coil winding machines of the type in which fine wire to be wound on small closed cores is stored in a circularly bent tube or shuttle of relatively large diameter which is threaded through the small closed core.

When a closed core is wound on such a machine, it is known that during the first half of the revolution of the ring tube or shuttle with respect to the core, a little more wire is pulled from the shuttle than is necessary for that turn on the core. As a result a wire loop forms during the remainder of the revolution and, due to centrifugal force, the loop tends to be thrown out of the machine and the last turn wound upon the core tends to loosen.

It has been customary, therefore, to guide the wire in these winding machines, after leaving the ring shuttle, between spring-loaded flanges or plates which resiliently clamp the wire to retard its displacement by centrifugal force and to prevent its loosening on the core. A disadvantage of such resilient guiding devices is that the spring pressure must be accurately adjusted for each wire size to avoid breakage of the wire.

Objects of this invention are to provide coil winding machines of the type stated which include rigid braking devices that do not require adjustment for different wire sizes to prevent loosening of the wire on the wound core or a kinking of the excess wire loop. More specifically, objects are to provide coil winding machines of the type stated which include rigid members spaced along and projecting from opposite sides into the path of the wire after it leaves the core, thereby to exert a braking action upon the wire to prevent it from loosening on the core and from inadvertent movement by centrifugal force.

These and other objects and the advantages of the in vention will be apparent from the following specification when taken with the accompanying drawings, in which:

Fig. 1 is a side elevation of a coil winding machine embodying the invention;

Fig. 2 is a section on line 2-2 of Fig. 3;

Fig. 3 is a section on lines 3-3 of Figs. 1 and 2;

Fig. 4 is a fragmentary plan of the entrance end of the brake bar of Fig. 3 as seen from below on removal from the grooved plate 5;

Figs. 5 and 6 are elevations of the respective devices for preventing a loosening of the last turn of wire wound upon the core, as seen when removed from the machine;

Fig. 7 is a somewhat schematic view of the same as seen when looking in the direction of the arrow VII; and

Fig. 8 is a horizontal section on line 8 -8 of Fig. 1.

In the drawings, the reference numeral 1 identifies a radially split and circularly bent tube constituting a ringshaped shuttle in which the winding wire W is stored. The ring shuttle is provided with exit means, which is shown schematically as a rod or roller 2 in an opening 3 in the shuttle, through which the wire W is withdrawn for winding upon a core C that may be supported upon a holder of desired type, for example a device as de- 2,761,629 Patented Sept. 4, 1956 scribed and claimed in my prior Patent No. 2,467,643.

For simplicity of description and illustration, it is assumed that the machine is of the type disclosed and claimed in my copending application Ser. No. 169,393, filed June 21, 1951, now Patent No. 2,699,902 of January 18, 1955, and reference is made to that application for a detailed description of the ring shuttle and the general structure of the winding machine.

As therein described, the ring shuttle is supported on and between opposed sets of beveled wheels 4 mounted on frame members 5, 6 having opposed surfaces closely adjacent and at opposite sides of the winding plane in which the wire is drawn upon rotation of the shuttle 1.

As distinguished from the machine described in the prior application, motion is imparted to the ring shuttle by two opposed cylindrical friction wheels 4, of which only one appears in Fig. 1, which are belt driven by a motor, not shown. The particular form of the ring shuttle and the means for supporting and driving the same are not critical, however, as the invention may be employed with different types of ring shuttle winding machines. j

The shuttle 1 is usually of substantially larger diameter than the core C which is to be wound and, if the shuttle turns clockwise, as indicated by the arrow, wire in excess of the amount required for one turn is drawn from the shuttle and the wire W remains taut only during the first half of each revolution of the shuttle 1, i. e., as the exit opening of the shuttle moves from within the core C into position I at which it is most remote from the core. On further rotation of the shuttle, this excess of wire forms a loop, as indicated by the dotted lines extending from the core C to the several positions IIV, and would be thrown radially outward from the space between frame members 5 and 6 by centrifugal force if no means were provided to prevent it in the last quadrant of movement of the opening 3 of the shuttle.

In accordance with this invention, a guiding action is imposed upon the loop which limits its movements to those due to the traction imposed upon the wire W by the shuttle 1. The last quadrantof the frame member 6 along which the exit opening 3 of the shuttle 1 moves as it approaches the core C is provided with parallel grooves 7 at opposite sides of a rib 8, and a bar 9 is mounted in a recess of frame member 5 by a screw 10, the bar having parallel flanges 11 which extend across the winding plane and project into the grooves 7. The wire W is thus transversely bent as the bight of the loop slides along the rib 8 and flanges 11, as shown in Fig. 2, and is thereby restrained from outward movement by centrifugal force.

The ends 11 of the ribs 11 are preferably conical to bend the wire W progressively to a flat wave form as it moves substantially parallel to itself beyond position III at Which an appreciable centrifugal force starts to develop when the shuttle 1 is rotated rapidly for high speed production of the wound cores. Since the wire loop enters the guide device at substantially position Ill, it is thus restrained from movement in a radial direction until it reaches position V at which it is collapsed to such small size that it can no longer swing outwardly.

The edges of the rib 8 and flanges 11 are rounded, as shown, and all surfaces contacted by the wire W are highly polished to reduce the frictional resistance to movement of the wire in a direction transverse to the radial action of centrifugal force.

The relative widths of the grooves 7 and flanges 11 are such that a relatively flat wave form is imposed upon the wire, and any one arrangement will be appropriate for a wide range of wire series. If the machine is to be employed for winding cores with wires of widely different sizes, provision is made for an adjustment of the flanges 11 to penetrate to a greater or lesser extent into the grooves 7, for example by means of a resilient backing for the bar 9, whereby the flanges 11 may be moved away from the grooved frame member 6 by tightening the screwltl. As shown in Figs. 2 and 3, the resilient backing is provided by a leaf spring 12.

The guide device is not limited to the illustrated construction in which a pair of flanges 11 project into linear grooves 7 since the number and the shapes of the complementary wire-bending elements may be varied without departure from the spirit of the invention.

A somewhat similar construction which operates, however, as both a guide and a tension-maintaining braking device is provided for preventing a loosening of the last turn wound upon the core C during travel of the, exit opening 3 of shuttle 1 from position I backto the core. Thin plates 15, 16 are supported in shallow recesses in the opposed faces of frame members 5 and 6 by shafts 15, 16, respectively, which permit a small angular adjustment of the plates for a purpose which will be explained later. A small tab 16a may be bent from or secured to the plate 16 to guide the wire W into the space between the plates 15 and 16 as the shuttle opening 3 leaves the core C.

The plate 15 has fixed thereto a rigid member 17 with a horn-shaped edge 18 which extends transversely of the winding plane and projects into an opening 19 in the plate 16, see Figs. 7 and 8. The edge 18 slopes smoothly downward from the point first contacted by the wire W to a notch 18 in which the wire is arrested at the level of, or slightly above, the top surface of the core C, see Fig. 7. The purpose of the supporting shafts 15', 16 is to permit angular adjustment of the plates 15, 16 by means, not shown, to position the notch 18' at an appropriate level in accordance with the thickness of the core to be wound.

When the exit opening 3 of the ring shuttle 1 reaches position I of Fig. 1, the tension on the wire W has drawn it down over the sloping edge 18 of the horn-shaped element and trapped it in the notch 18', whereby it can not bend upwardly and loosen on the core as the excess wire drawn from the shuttle forms a loop during the continued rotation of the shuttle.

The plates 15, 16 and the edge 18 of the horn-shaped element are highly polished to reduce friction, and the width of the opening 19 is at least twice the thicknessof the element 17 to impart a relatively flat transverse wave form to the wire. A single adjustment of the element 17 is appropriate for all wire sizes as the retarding effect of the transverse bend varies directly with the wire thickness, and is obtained without imposing a substantial longitudinal stress upon the wire.

So far as I am aware, it is broadly new in the winding of closed ring cores on winding machines of the ring shuttle type to restrain the excess wire from inadvertent movement by imparting a transverse Wave form to the wire, and it is therefore to be understood that various modifications may be made in the guiding elements as herein shown and described without departing from the spirit and scope of the invention as set forth in the following claims.

I claim:

1. A winding machine for winding wire upon closed ring cores comprising a ring-shaped shuttle of larger diameter than the cores for storing the winding wire, exit means on the shuttle from which the stored winding wire may be withdrawn, said shuttle being radially split for threading through a core to be wound, means for supporting and rotating said shuttle through a core to be wound, whereby an excess of wire is drawn from said shuttle as said exit means moves away from the core during each rotation of the shuttle, said shuttle supporting means including a pair of frame members having opposed surfaces between which the excess wire is drawn into loop form by said shuttle, and guide means to limit movements of said wire to those due to the tractive force exerted thereon by said shuttle, said guide means comprising a longitudinal groove in said'opposing surface of one of said frame members and a bar secured to the other frame member and projecting into said groove to impose a transverse bend upon said excess wire in a plane normal to its path of movement.

2. A winding machine as recited in claim 1, wherein the ends of said bar are conical.

3. A winding machine for winding wire upon closed ring cores comprising a ring-shaped shuttle oflarger diameter than the cores for storing the winding wire, exit means on the shuttle from which the stored winding wire may be withdrawn, said shuttle being radially split for threading through a core to be wound, means for supporting and rotating said shuttle through a core to be wound, whereby an excess of wire is drawn from said shuttle said exit means moves away from the core during each rotation of the shuttle, said shuttle supporting means including a pair of frame members having op posed surfaces between which the excess wire is drawn. into loop form by said shuttle, and guide means to limit movements of said wire to those due to the tractivc force exerted thereon by said shuttle, said guide means comprising grooves in said opposing surface of one of said frame members, said grooves extending parallel to each other and to the direction of travel of the bight of the loop along the same, and a bar secured to the other frame member and having parallel flanges projecting into the respective grooves to impose a transverse bend upon said excess wire in a plane normal to its path of movement.

4. A winding machine as claimed in claim 3, wherein said grooves and bar are located in the last quarter of the circle described by said exit means on said rotating shuttle as said exit means approaches the core to be wound.

5. A winding machine as claimed in claim 3, in combination with means to adjust the extent to which said flanges project into said grooves.

6. A winding machine for winding wire upon closed ring cores comprising a ring-shaped shuttle of larger diameter than the cores for storing the winding wirc, exit means on the shuttle from which the stored winding wire may be withdrawn, said shuttle being radially split for threading through a core to be wound, means for supporting and rotating said shuttle through a core to be wound, whereby an excess of wire is drawn from said shuttle as said exit means moves away from the core during each rotation of the shuttle, said shuttle support ing means including a pair of frame members having opposed surfaces between which the excess wire is drawn by said shuttle, and guide means to limit movements of said wire to those due to the tractive force exerted thereon by said shuttle, said guide means including a hornshaped element secured to one of said frame members and projecting laterally into the winding plane to im pose a transverse bend upon said excess wire in a plane normal to the winding plane.

7. A winding machine as recited in claim 6, wherein the edge of the horn-shaped element slopes smoothly from the point thereof first engaged by the winding wire to and beyond the winding plane.

8. A Winding machine as recited in claim 7, wherein the edge of the horn-shaped element is provided with a notch in which the transverse bend of the winding wire seats.

9. A winding machine for winding wire upon closed ring cores comprising a ring-shaped shuttle of larger diameter than the cores for storing the winding wire, exit means on the shuttle from which the stored winding wire may be withdrawn, said shuttle being radially split for threading through a core to be wound, means for supporting and rotating said shuttle through a core to be wound, whereby an excess of wire is drawn from saidshuttle as said exit means movesaway from the core during each rotation of the shuttle, said shuttle supporting means including a pair of frame members having opposed surfaces between which the excess wire is drawn by said shuttle, and guide means to limit movements of said wire to those due to the tractive force exerted thereon by said shuttle, said guide means including a hornshaped element secured to one of said frame members and projecting laterally into the winding plane, and a cooperating plate secured to the other frame member and extending parallel to the winding plane, said cooperating plate having an opening therethrough into which said horn-shaped element projects thereby to impose a transverse bend upon said excess wire in a plane normal to the winding plane.

10. A winding machine as recited in claim 9, wherein the width of the opening in said cooperating plate is at least twice the thickness of the horn-shaped element.

References Cited in the file of this patent UNITED STATES PATENTS 

